neji improved a lot he mastered two elements, because he became a jounin. Of course sasuke improved his skills more than anyone else but he has a cursed seal and he took the help of orochimaru. just judging by pure training i would say neji improved at most

narutos improvment is still in progress but judging by his skills two and a half year earlier he dindt improve that much his chakra control is still poor compared to the other nins and only developed a new rasengan. so narutop didnt improved a lot at all.